Homeowners install fish ponds in their yards and gardens to create a peaceful, beautiful setting. Sitting near the outdoor fishpond and watching the fish swim through it is very relaxing. The admiring stares and glimpses of family friends and guests, makes you feel so good inside as they compliment your choices of flowers, fish and pond accessories. The hard work all feels so good and so worthwhile. A fish-pond is its own delicately balanced eco system. Over time, exposure to weather conditions and the accumulation of fish poop and urine, your once beautiful pond can become a green, slimy, stinky eyesore unless you maintain a cleaning schedule.

Removing the debris, poop and other nasties will help to keep your swimming friends happy and healthy. Leaving the pond to take care of itself is not an option. Urine left in becomes toxic as the fish urine contains ammonia. Excessive amounts of ammonia is deadly to fish. Algae left to grow and flourish depletes it of oxygen, which again is dangerous and deadly to your fish and other small animals living in the garden-pond including frogs, toads or snails. Typically, outdoor fish ponds require a once or at worst twice per year thorough cleaning to keep your water plants and fish happy, healthy and swimming along.

Routine Fish-Pond Maintenance

Skim the surface of the fish pond with a swimming pool net to remove floating twigs and leaves three to four times per week.

Don’t worry if it is a light green color or has a greenish tinge, this is normal and to be expected. It is part of the balance of nature.

If it is filtered, change the filtering material anywhere from every two week to every four weeks depending on the amount of debris you find in it and the number of plants.

That’s really all the routine maintenance an outdoor pond requires.

Fish Pond Deep Cleaning – At Least Once Per Year

Cleaning the fish pond is a messy and dirty spring cleaning project. Although messy, it is necessary if you want a beautiful pond with swimming fish rather than floating fish.

Rinse a couple of buckets or a kiddie pool with a spray of water from a garden hose. Don’t use any soaps or chemical cleaners to scrub them clean. The soap and chemicals are dangerous to the inhabitants of the pond.

Place the buckets or kiddie pool in a shaded area to keep it from overheating and to create a lower stress environment for the fish while you are cleaning the fish pond.

Fill up a few buckets or a kiddie pool halfway with clear water and the remainder of the way with buckets of the garden-pond water. Let it stand and acclimate for 24 hours. The 24 hours period allows excess chlorine to dissipate and it to reach the same temperature as the pond water.

Pull on a pair of hip waders or tall rubber boots because you are going to have to get your feet wet to get the fish pond clean.

Scoop the fish, frogs, toads or snails out of the garden-pond with a fish net and place them gently into the buckets or kiddie pool.

Gently remove the plants from the edge -- and set them in one of the buckets in the shade. If you are using a kiddie pool, you can place the plants into the pool with the fish.

Pick up the floating plants including any pots they are in. As you are removing plants gently spritz them with a spray of water from a spray bottle to remove any slime or algae.

Slightly submerge a bucket into the topmost water-drains into the bucket. Once the bucket is filled set it aside in the shade. The top part of it is typically cleaner than the bottom where fish poop and algae tend to accumulate. Reserve a few buckets of pond water for later.

Bale it out of the pond with buckets or remove it with a siphon. Avoid using a strong powered siphon because you may harm small animals living in the slimy bottom. Don’t discard it down the drain. Water your indoor and outdoor plants with the garden-pond water, your plants will love you for the extra nutrients. As you are removing it keep your eyes open for small toads, frogs or snails. If you find them scoop them up and place them in one of the buckets sitting in the shade.

Remove rocks and stones and set them on a tarp. Use a garden hose to spray algae and dirt off the rocks. Scrub the rocks lightly with a nylon scrub brush. Don’t attempt to remove all of the algae and other growth from the stones and rocks, some of that helps to keep the eco system in the pond balanced.

Continue to remove water from the fish pond until the pond has about 4 to 6 inches of water. Spray the sides of the pond with water from a garden hose. Gently rub the sides with a soft bristled scrub brush to loosen and remove all debris. Rinse the sides allowing the dirty walls to run into the bottom of the pond.

Vacuum the algae, fish poop and gunk from the bottom of the fish pond with a wet dry vacuum. Rinse the bottom clear water and vacuum a second time.

Wipe down filter hoses and rinse them. Clean the aerators and water filters according to the manufacturer’s directions.  

Put the stones and rocks back into the pond.

Fill the pond about ¼ of the way with water from a garden hose. Add a dechlorinator to it. Take a water sample to your local fish store and have them test it for ammonia and nitrates. If it has excess amounts of either buy a conditioning treatment for it to return the balance.

Put the bottom and submerged plants back into it. Add the floating plants next. Add it from the buckets slowly into the pond. Let it acclimate for an hour or two. Begin returning toads, frogs and snails. Add the fish back to the pond using the same measures you took to acclimate them to the pond when you first bought them to avoid over stressing the fish.

Slowly add the remaining water from the buckets or kiddie pool until the pond is filled. If it level needs to be higher, fill some buckets with water and let them remain outside for 24 hours before slowly adding it into the fish pond.